# Population size when creating a Study

I have a question about setting the Population size value when creating a Study.
The Autodesk help page says “A rule of thumb is to set the population size to at least three times the number of inputs.”
However, when I actually try to set it, the Study screen in Generative Design says as an issue that “Population Size must be equal or greater than 4 and a multiple of 4.”

I would like to know how to determine the value of Population size.

This is a good guideline, though in some cases you may want a multiple is ten or two or some unrelated number. It’s a rule of thumb not a steadfast certainty after all.

So as the value has to be divisible by four, round up to the next multiple of four. I.E if you have 3 inputs, multiply that by 3 to get 9, the next multiple of four is 12, so use 12 to start with. That said generally I don’t recommend dropping below 20 - again these are guidelines, and you need to learn what works for the type of problems you are solving.

1 Like